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1.
Sensors (Basel) ; 18(4)2018 Apr 21.
Article in English | MEDLINE | ID: mdl-29690536

ABSTRACT

One of the critical missions for next-generation wireless communication systems is to fulfill the high demand for massive Machine-Type Communications (mMTC). In mMTC systems, a sporadic transmission is performed between machine users and base station (BS). Lack of coordination between the users and BS in time destroys orthogonality between the subcarriers, and causes inter-carrier interference (ICI). Therefore, providing services to asynchronous massive machine users is a major challenge for Orthogonal Frequency Division Multiplexing (OFDM). In this study, OFDM with index modulation (OFDM-IM) is proposed as an eligible solution to alleviate ICI caused by asynchronous transmission in uncoordinated mMTC networks. In OFDM-IM, data transmission is performed not only by modulated subcarriers but also by the indices of active subcarriers. Unlike classical OFDM, fractional subcarrier activation leads to less ICI in OFDM-IM technology. A novel subcarrier mapping scheme (SMS) named as Inner Subcarrier Activation is proposed to further alleviate adjacent user interference in asynchronous OFDM-IM-based systems. ISA reduces inter-user interference since it gives more activation priority to inner subcarriers compared with the existing SMS-s. The superiority of the proposed SMS is shown through both theoretical analysis and computer-based simulations in comparison to existing mapping schemes for asynchronous systems.

3.
J Assist Reprod Genet ; 28(6): 495-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21647639

ABSTRACT

PURPOSE: To determine if IVM of oocytes from unstimulated cycle is a treatment option for patients who did not deliver after standard IVF-ET. METHOD: Twenty three women with PCO, thirteen of them with normal cycles and all <35 years old, who failed IVF served as their own control. During the control IVF cycle patients were stimulated with 1730.7 ± 639.5 IU recombinant FSH, a long Buserelin acetate protocol was used and embryo transfer was performed on day 2 or 3 after ICSI. After failed IVF immature oocytes were aspirated transvaginally from antral follicles during spontaneous menstrual cycle. Embryo transfer was performed 2 or 3 days later. RESULT: 11.4 ± 4.8 mature oocytes and 6.7 ± 3.2 embryos were produced with IVF, which served as the control, compared to 9.7 ± 4.5 mature oocytes and 6.2 ± 3.2 embryos with IVM. There was one clinical pregnancy in the IVF group which did not result in a live birth where as five singleton and one pair of twins with healthy live births and one miscarriage in the IVM group. CONCLUSION: IVM does not involve ovarian stimulation with possible financial and health consequences. It may be an useful treatment after unsuccessful IVF.


Subject(s)
Follicle Stimulating Hormone/therapeutic use , In Vitro Oocyte Maturation Techniques/methods , Infertility, Female/therapy , Oocytes/growth & development , Polycystic Ovary Syndrome/complications , Sperm Injections, Intracytoplasmic/methods , Adult , Buserelin/therapeutic use , Embryo Transfer/methods , Female , Follicle Stimulating Hormone/administration & dosage , Humans , Infertility, Female/etiology , Pregnancy
4.
Fertil Steril ; 95(7): 2274-8, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21496799

ABSTRACT

OBJECTIVE: To evaluate the association between follicular fluid levels of propeptide and mature forms of growth differentiation factor (GDF) 9 and bone morphogenetic protein (BMP) 15 with subsequent oocyte and embryo quality. DESIGN: Prospective clinical study. SETTING: University hospital. PATIENT(S): Eighty-one infertile patients who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). INTERVENTION(S): The expression levels of the propeptide and mature forms of follicular fluid GDF9 and BMP15 were determined by western blot analysis. The levels of follicular fluid hormones (FSH, E2, and P) were measured with automated chemiluminescent enzyme immunoassays. MAIN OUTCOME MEASURE(S): The relationships between the levels of GDF9 and BMP15, hormones, oocyte maturation, and embryo quality. RESULT(S): Mature GDF9 levels were significantly correlated with the nuclear maturation of oocytes. The mean mature GDF9 level was 4.87±0.60 in the high-embryo-quality group and 1.45±0.81 in the low-embryo-quality group. There were no statistically significant differences in embryo quality among the patients regarding propeptide GDF9 and BMP15 expression status. There was a negative correlation between follicular fluid levels of P and the mature form of GDF9. CONCLUSION(S): Higher mature GDF9 levels in the follicular fluid were significantly correlated with oocyte nuclear maturation and embryo quality.


Subject(s)
Blastomeres/physiology , Bone Morphogenetic Protein 15/analysis , Fertilization in Vitro , Follicular Fluid/chemistry , Growth Differentiation Factor 9/analysis , Oocyte Retrieval , Oocytes/physiology , Adult , Blotting, Western , Chi-Square Distribution , Cleavage Stage, Ovum , Embryo Culture Techniques , Estradiol/analysis , Female , Follicle Stimulating Hormone, Human/analysis , Hospitals, University , Humans , Immunoenzyme Techniques , Linear Models , Progesterone/analysis , Prospective Studies , Sperm Injections, Intracytoplasmic , Treatment Outcome , Turkey
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